Push-buttons



5 ROHACS PUSH-BUTTONS Nov. 1, 1955 Filed June 1, 1953 RSkiiiait 3 UnitedStates Patent 2,722,579 PUSH-BUTTONS Etienne Rohacs, Saint-Gratien,France, assignor to Societe dApplications des Machines Motrices,Boulogne-Blllancourt, France Application June 1, 1953, Serial No.358,874

Claims priority, application France June 5, 1952 8 Claims. (Cl. 20077)The invention relates to push-buttons, more particularly to push-buttoncontactors, and its main purpose is to provide a muscular sensation toindicate that the contact has been eifectively accomplished.

Another aim of the invention is a push-button contactor in which theclosing and opening of the contacts is effected very abruptly.

The push-button according to the invention comprises a movable membercarrying the junction member of two fixed contacts or, if necessary, themovable contact, the said movable member being provided with a sphericalor cylindrical surface or, more generally, a curved surface having asymmetry plane and, on both sides respectively of the symmetry plane, atangential plane parallel to the symmetry plane and two springs one oneach side of the said symmetry plane, the said springs exerting apressure in such manner that the axial component changes its directionwhen the contact points pass the tangential points of the saidtangential planes parallel to the symmetry plane.

In the accompanying drawings:

Figure 1 is a vertical section on the symmetry plane of the operatingsurface of a push-button according to the invention;

Figures 2, 3 and 4 are detailed views of a member of the saidpush-button.

In Figures 1, 2, 3 and 4, 1 designates the button on which the action isexerted against the action of a coil spring 2 which bears on a member 3.The totality is housed in a cylindrical casing 4 comprising a shoulder 5which forms a stop for the button 1, and a semi-cylindrical groove 6 forthe packing ring 7.

For the purpose of easy assembly the member 3 is preferably formed intwo symmetrical parts.

The mobile member 8 carries the conducting bridge 9 which simultaneouslyconstitutes a supporting surface by means of which the member 8 seats onthe member 10. The shoulder 11 of the member 8 maintains the bridge 9 onthe shank 8 against the guide member 12 but with sufiicient clearance toallow the bridge the few degrees of oscillation necessary for thecontact to be free.

The movable member 8 carries the operating surface 13 on which aresymmetrically supported two leaf-springs 14 which are fixed in anysuitable manner to the button 1.

The surface 13 is pherical or cylindrical, the axis of the cylinder thusbeing perpendicular to the plane of the figure, the springs 14, whichmay be helical or of the leaf type, being supported on the cylindricalsurface 13 in the manner of a generatrix. The springs 14 are shaped attheir ends in such manner as to have a cambered portion 15 in order tocreate an axial component of the pres sure exerted in oppositedirections on both sides of the symmetry plane of the cambered portion.There may be provided in the region of the cambered portion a gap tofacilitate the passage of the shank 8.

The operation is as follows:

When the button 1 is pressed, the axial component of the pressureexerted on the surface 13 by the springs 14 tends to press the member 8on to its seating; when the cambered portion passes by the dead centrethe change of direction of the axial component causes the mobile member8 to move strongly upwards and the bridge 9 will close the circuitabruptly by joining the terminals 16 and 17. The travel of the button islimited by the stop 21.

When the button 1 is released, the spring 2 returns the springs 14upwards while urging the bridge 9 against the terminals during theinitial period of travel. When the dead centre has been passed, theaxial component causes the member 8 abruptly to descend and separatesthe bridge 9 from the terminals, thus opening the circuit.

The simplicity of the construction is due to the special shape of themember 10. The latter is provided for the purpose of locking the flatconductors 18, 19 between itself and the bell-shaped member 3.

However, the member 10 might be provided for the purpose of locking theflat conductors between itself and the casing 4.

The said member 10 comprises a moulding 20 forming a shoulder for thepacking ring 7. It likewise comprises suitable gaps which correspond tothe thickness of the conductors. The terminals 16 and 17 are obtained bymerely bending the conductors between the members 3 and 10. The member10 further has groovings suitable for the bridge 9 and for guiding themember 12.

Assembly is easily effected.

After an easy assembly of the members 8, 9, 12, then of 3, 10, 18, 19,the whole is pushed against the action of the spring 2 until the packingring can be placed in position, while dismantling is also easy, it beingsuflicient to release the packing ring.

The simplicity of assembly is therefore obtained by using the action ofthe opposing spring of the button I for the purpose of bearing the stopof the said opposing spring and bearing the contact-carrier memberagainst a key member, for example a packing ring.

I claim:

1. In an electrical push button having a housing through which centrallythereof the axis of the push button extends generally vertically, amovable shank in said housing coaxial with said push button andcomprising at one extremity a curved surface having a symmetry plane andtwo tangential planes parallel to said symmetry plane and to said axis,said shank having guide means and carrying a contact member at a remotedistance from said curved surface, said push-button carrying a pair ofsprings disposed parallel to said tangential planes, said springsexerting a yielding pressure in opposite directions on said curvedsurface.

2. In an electrical push button switch having a housing through whichcentrally thereof the axis of the push button extends generallyvertically, a movable shank in said housing coaxial with said pushbutton and comprising at one extremity a curved surface having asymmetry plane and two tangential planes parallel to said symmetry planeand to said axis, said shank carrying guide means and carrying a contactmember at a remote distance from said curved surface, said push buttoncarrying a pal. of springs disposed parallel to said tangential planes,said springs having a curved portion in front of said curved surface andexerting by means of said curved portion a yielding pressure in oppositedirections on said curved surface.

3. In an electrical push button switch having a housing through whichcentrally thereof the axis of the push button extends generallyvertically, a movable shank in said housing coaxial with said pushbutton and comprising at one extremity a sphere and carrying a contactmember at a remote distance from said sphere, guide means for saidshank, said push button carrying a pair of springs disposed tangentiallyto saidsphere, said springs exerting a yielding pressure in oppositedirections on said sphere.

4. In an electrical push button switch having a housing through whichcentrally thereof the axis of the push button extends generallyvertically, a movable shank in said housing coaxial with said pushbutton and comprising at one extremity a sphere and carrying a contactmember at a remote distance from said sphere, guide means for saidshank, said push button carrying a pair of springs disposed tangentiallyto said sphere, said springs having a curved portion in front of saidsphere and exerting by means of said curved portion a yielding pressurein opposite directions on said sphere.

5. In an electrical push button switch having a housing through whichcentrally thereof the axis of the push button extends generallyvertically, a movable shank in said housing coaxial with said pushbutton and comprising at one extremity a cylindrical surface having itsaxis perpendicular to said first axis and carrying a contact member at aremote distance from said cylindrical surface, guide means for saidshank, said push button carrying a pair of springs tangential to saidcylindrical surface and exerting a yielding pressure in oppositedirections on said cylindrical surface.

6. In an electrical push button switch having a housing through whichcentrally thereof the axis of the push button extends generallyvertically, a movable shank in said housing coaxial with said pushbutton and comprising at one extremity a cylindrical surface having itsaxis perpendicular to said first axis and carrying a contact member at aremote distance from said cylindrical surface, guide means for saidshank, said push button carrying a pair of springs disposed tangentiallyto said cylindrical surface, said springs having a curved portion infront of said cylindrical surface and exerting by means of said curvedportion a yielding pressure in opposite directions on said cylindricalsurface.

7. An electrical push button switch comprising in combination acylindrical housing, a push button having its axis extending into saidhousing, stop means to limit the movement of said push button, acylindrical hollow and closed body of insulating material disposed insaid housing, a spring in said housing between said hollow body and saidpush button, a movable shank coaxial with said casing and having a partextending into said hollow body and comprising at its extremity outsideof said hollow body a curved surface having a symmetry plane and twotangential planes parallel to said symmetry plane and to the axis of thepush button, said shank carrying a contact member on the part inside ofsaid hollow member, guide means for said shank, said hollow memberhaving fixed terminals therein to co-operate with said contact member,said push button carrying a pair of springs parallel to said twotangential planes, said springs having a curved 7 portion in front ofsaid curved surface and exerting by means of said curved portion ayielding pressure in opposite directions on said curved surface.

8. An electric switch as claimed in claim 7, the hollow body having acylindrical member, the terminals being locked between said cylindricalmember and said hollow member, said cylindrical member having a coaxialgroove co-operating with the shank in its axial movement.

References Cited in the file of this patent UNITED STATES PATENTS1,689,852 Batcheller Oct. 30, 1928

